[18] Gay, _Quarterly Journal of Economics_ (1902-1903), vol. xvii, p. 587. [19] Pollard, _Reign of Henry VII_ (London, 1913), vol. ii, pp. 235-237. [20] More, _Utopia_ (Everyman edition), p. 23. [21] _Ibid._, p. 24. [22] _Outlines of the Economic History of England_ (London, 1908), p. 118. [23] _Growth of Eng. Ind. and Commerce_ (Cambridge, 1892), p. 180. [24] _England's Industrial Development_ (London, 1912), p. 247. [25] _English Economic History_ (New York, 1893), part ii, p. 262. [26] Carew, _Survey of Cornwall_ (London, 1814), p. 77. [27] Cunningham, _Growth of English Industry and Commerce, Modern Times_, 1903, part i, p. 101. [28] Lennard, _Rural Northamptonshire_ (Oxford, 1916), p. 87. For other examples, _cf. infra_, pp. 84, 99-101. [29] Leonard, _Royal Hist. Soc. Trans._, 1905. Gonner in _Common Land and Inclosure_ covers much the same ground, but does not bring out as clearly the extent to which the seventeenth century enclosures were accompanied by conversion of tilled land to pasture. [30] Tawney, _Agrarian Problem in the Sixteenth Cen._ (London, 1912), p. 391. [31] _Royal Hist. Soc. Trans._ (1905), vol xix, note 1, p. 113. [32] _Ibid._, pp. 116-117. [33] Rogers, _History of Agriculture and Prices_, vol. iv, p. 757. [34] _Cf. infra_, p. 98. [35] Levett and Ballard, _The Black Death_, p. 129. [36] _Cf. infra_, p. 82. [37] Tawney, _op. cit._, p. 220, note 1. [38] _Infra_, p. 78, 81, 98-9. CHAPTER II THE FERTILITY OF THE COMMON FIELDS Up to this point attention has been given chiefly to the theory that the enclosure movement waxed and waned in response to supposed fluctuations in the relative prices of wool and grain, and it has been found that this theory is untenable. It is now necessary to consider more closely the true cause of the conversion of arable land to pasture--the declining productivity of the soil--and the cause of the restoration of this land to cultivation--the restoration of its fertility. The connection between soil fertility and the system of husbandry has been explained by Dr. Russell, of the Rothamsted Experiment Station: